Can hydroxyurea serve as a free radical scavenger and reduce iron overload in β-thalassemia patients?

In this study, we hypothesize that hydroxyurea could provide an additional benefit as a free radical scavenger and/or iron chelator in -thalassemia patients with iron overload. Twenty-one -thalassemia intermedia patients who presented between 3 and 17 years but later required regular blood transfusions were enrolled for hydroxyurea therapy for a year. Fourteen patients responded to the therapy with hemoglobin levels maintained above 7.5g/dl without transfusions. Hydroxyurea was discontinued after 6 months in seven patients who did not respond to the therapy and had to be continued on regular blood transfusions. We observed a statistically significant decrease in serum ferritin levels from 4194 +/- 4850ng/ml to 2129 +/- 2380ng/ml among the responders and from 2955 +/- 2909ng/ml to 2040 +/- 2432ng/ml among the non-responders and statistically significant decrease in labile iron pool from 18678.7 +/- 10067.4 mean fluorescence intensity (MFI) to 14888.5 +/- 5284.0MFI among responders and from 17986.3 +/- 9079.8MFI to 15634.8 +/- 8976.9MFI among the non-responders after therapy. Phosphatidylserine externalization also showed a statistically significant decrease from 44.2 +/- 22.2MFI to 16.6 +/- 6.7MFI among the responders and from 46.9 +/- 33.1MFI to 39.8 +/- 7.4MFI among the non-responders along with a statistically significant decrease in the levels of reactive oxygen species from 72.8 +/- 35.5MFI to 29.0 +/- 8.3MFI among the responders and from 80.9 +/- 41.4MFI to 40.5 +/- 15.8MFI among the non-responders after therapy. A statistically significant increase in reduced glutathione levels was also observed from 430.8 +/- 201.1MFI to 715.5 +/- 292.4MFI among the responders and from 359.6 +/- 165.6MFI to 450.3 +/- 279.5MFI among the non-responders after therapy. This suggests the possible additional role of hydroxyurea as a free radical scavenger and/or iron chelator but requires a larger study for substantiation.